The present invention relates to an improvement for simplifying the construction of a grass cutting system having a cutter blade rotatable on a vertical axis and a grass catcher for collecting grass clippings, and to riding type and walking operator type lawn mowers equipped with an improved grass cutting system.
Conventional walking operator type lawn mowers, generally, comprise a vehicle body including ground wheels, an engine and a steering handle. The vehicle body carries a cutting blade, and a grass catcher consisting of a net bag or a plastic box mounted, for example, on a rear face of the vehicle body. Where the grass catcher is mounted on the rear face or the like of the vehicle body, it is necessary to transmit grass clippings tangentially of the locus of rotation of the cutting blade. Thus a grass transmitting passage takes the form of a duct extending approximately horizontally and rearwardly of the vehicle body.
With the type of lawn mower that transmits grass clippings horizontally, however, the grass to be cut could be turned sideways by air currents flowing horizontally, thereby impairing a desired grass cutting operation. In order to eliminate this inconvenience, a construction has recently been developed, as disclosed in Japanese Utility Model Publication Kokai No. 62-17830, wherein a cutting blade produces upward air currents to maintain in an upright orientation the grass to be cut. According to this construction, grass clippings are transmitted upwardly by the upward air currents, without using a duct or the like, to a grass catcher disposed above the cutting blade.
Further, the grass catcher in the construction disclosed in the Japanese publication is in the form of a ring in plan view. The grass clippings move upward with the air currents through the center of the grass catcher, and are thereafter delivered to peripheral positions of the grass catcher.
Where the grass catcher is in the form of a ring, however, the bottom surface thereof must be formed into a smooth horn shape. This grass catcher, therefore, is not only complicated in construction and troublesome to manufacture but presents difficulties to enlargement of its grass storing capacity.